Differential Diagnosis Between Neurodegenerative Dementia Disorders and Parkinson’s Disease Using 99mTc-HMPAO SPECT

Introduction and Objective: To investigate perfusion in dementia and Parkinson's disease (PD) we performed 99m Tc-HMPAO brain SPECT with semiquantitative analysis of Brodmann areas in different aged patients. Materials and Methods: We retrospectively evaluated 104 patients, 30 with Alzheimer's disease (AD), 26 with frontotemporal dementia (FTD), 25 with mild cognitive impairment (MCI), 23 with PD, undergoing 99m Tc-HMPAO brain SPECT. SPECT data of 3D ROIs of predefined Brodmann's area templates were compared with those of a database of age and sex-matched healthy subjects. Median values and inter-quartile ranges were used to summarize ROIs of Brodmann areas (L= left, R= right) in the different groups; Kruskal-Wallis test evaluated difference between medians (p< 0.05 as level of significance). Results: Different Brodmann areas were significantly hypoperfused in the different pathological categories. Both Areas 37 (temporal gyrus) and 39 (angular gyrus) of AD patients were hypoperfused (p<0.05) compared with MCI and FTD, both Areas 40 (supramarginal gyrus) and Area 39 L of AD patients were (p<0.01) hypoperfused comparing with PD; in FTD both Areas 47 (frontal association cortex) showed significantly decreased (p<0.05) perfusion compared with MCI and Area 11 R (frontal-orbital gyrus) comparing with PD. Conclusion: Perfusion impairment of specific parietal and temporal areas characterized AD, while frontal area hypoperfusion was present in FTD. No specific hypoperfusion pattern was evident for MCI and PD.